A Novel Single Helix Magnetic Lead Screw for Wave Energy Converter

A new type magnetic lead screw (MLS) is proposed in this paper. The proposed magnetic lead screw is assembled with a single helix permanent magnet (PM) on the translator, and the rotor adopts double helical PMs which is as same as the traditional MLS. This new structure of magnetic lead screw has many advantages, for example, when the proposed MLS is applied to the wave energy power generation system, and without changing its size, the proposed MLS can not only save a lot of PM consumption, but also adjust its maximum thrust by directly adjusting the width of the permanent magnet to adapt to different sea areas. In addition, the proposed MLS has a higher force density. Finally, compared with the traditional MLS, this new type of MLS also has the advantage of fast startup speed. For the proposed MLS, it is analyzed by the two-dimensional (2-D) finite element method (FEM), since the results of 2-D FEM simulation are almost the same as those of three-dimensional (3-D) finite element method (FEM). Additionally, the 3-D FEM is time-consuming. To verify the advantages of the proposed MLS, the performance of the proposed MLS is compared with the traditional MLS and the reluctance-based MLS (RBMLS). At last, the impact of different important parameters on the performance of the proposed MLS are analyzed. It provides a new option for the application of MLS in wave energy power generation systems.